Radio receiving device with distant control



Jan. 21, 1936. E ANDREWS RADIO RECEIVING DEVICE WITH DISTAN'i CONTROL 7 3 Sheets-Sheet 1 Y Filed March 20, 1928 @WW-w aim- Jan. 21, 1936. E'. F; ANDREWS 2,028,429

' RADIO RECEIVING DEVICE WITH DISTANT CONTROL I Filed March 20, 1923 s Sheets-Shet 2 g PM'JMW',

all'bmcya Jan".-2l, 1936. E. F. ANDREWS RADIO RECEIVING DEVICE WITH DISTANT CONTROL Filed March 20, 1923 5 Sheets-Sheet 3' Patented Jan. 21, 1936 r l g g-28A;

UNITED STATES PATENT OFFICE RADIO RECEIVING DEVICE WITH DISTANT CONTROL Edward F. Andrews, Evanston, 'Ill., assignor to The Andrews-Hammond Corp., Chicago, 111., a corporation of Illinois Application March 20, 1928, Serial No. 263,005

' 18 Claims. (01. 250-14) My invention relates to a radio receiving apfrequency amplifier, power devices, and loud paratus and particularly to a radio receiving apspeaker are of such a heavy or bulky nature as paratus in which the power devices are sepnot to allow them to be practically portable as a arated from the radio frequency tuning means unit. Y

which are positioned in a portable container It is a great advantage to have a small, confully transportable about a room or about a venient, portable and easily handled floor unit, house. In my device as herein shown the radio which can be located, at the will of the operator, frequency amplifier and detector and tuning near any chair or couch which he may Wish to means of a radio set are positioned preferably occupy, to permit tuning without the necessity o in a small stand or container. For example the of arising. A .floor stand of the type herein o radio set proper may be located in an enlarged shown lends itself particularly readily to a base which may rest upon the floor, and the decorative simplicity of design and can be made control means for adjusting frequency and voldecorative without housing it in an expensive, ume and for stopping and starting actuation of obtrusive, heavy and Space Occupying piece-0f the set are located in the upper portion of the furniture. Th p w box in any cases, need 15 stand, preferably at such a height above the not be decorative at all, and can belocated at floor as to be convenient for a seated, standing any inconspicuous space, or even in a closet, or reclining operator. In the form herein shown unless, as in s forms herein ow the l u a stem or tube projects upwardly from the enspeaker. is associated with it.

.20 larged base and at the upper end of the tube My improved type of radio receiver constitutesao are positioned the control means and, if desired, a hi hly adva ta u way of nst uctin a a handle for moving the portable unit about. r d y Portable radio Set, particularly W e e t The stand and the radio set parts therewithin part are too avy r lky to be pl d'in a are connected by a multi-conductor cable to singl container s in my e -p app ati n a fixed or semi-portable housing containing, for Serial No. 263,007, Patent No. 1,922,008, August example, the audio amplifier and the power sup- 3, or where is desired to ve a ud ply device for operating the complete radio set, ne k r l a at some di an e from the onincluding that portion of it located in the port- ,trols of the set, and still have the control portable container. The portable stand or container a w v t ud sp ake ay be assomay be carried from place to place within a c ated w th er unit- 30 range determined by the location of the fixed Further objects will appear from time to time container or power box andthe length of the in t e Cou Of the Specification and Claimscable connecting the power box to the stand. I illustrate my invention more or less dia- The distribution of the parts of the set between grammatically in the accompanying drawings,

the two containers may be somewhat varied but wherein- 35 I show herein the antenna and ground system Figure 1 is a perspective view of a form of my as connected to the fixed or semi-portable condevice; tainer or power box, with the leads run to the Figures 2 and taken together, illustrate av rradio frequency end of the set located in the ti'cal section of the portable unit shown at the a0 stand through the flexible conductive connec-. left of Figure 1; andtion. Figures 4 and 5, taken together, illustrate the I have determined by practical test and operawiring diagram of the two units, Figure 4 being tion that no serious interference occurs from the diagram for the portable unit and Figure 5 running the various leads and the power source for the fixed or semi-portable unit or power box.

if) connections in the same cable. This is par- Like parts are indicated by like characters ticularly true if the ground connection is made throughout the specification and drawings. in the form of a braided wire sheath and the de- Referring to the drawings, A indicates a base tector lead run inside of the sheath. The cable or floor contacting member and A a plate posiis not particularly sensitive to body capacity or tioned upon and spaced above the base A, for so proximity to metal objects, and the operation of example by the vertical supports A Mounted the radio and audio frequency amplifiers of the in the'space between the plate and the base and set is entirely satisfactory. But in many cases it between the vertical supports, and supported on is preferable to shield some of the connections, the plate, are a gang of three condensers, genas below set forth. This particular construction erally indicated as A each including the usual is of greateadva'ntaggl e p i l W1 ike-aud o rotor and stator plates. The rotor plates are fi C C indicate the usual type of tube socketsv and C C shielded inductances of the usual type. The wiring diagram or connections are fully illustrated in Figure e, and need not be described in connection with the description of the structure of Figures 1, 2 and 3'.

D indicates a transformer adapted to supply low voltage alternating current to the tube filaments. Since the particular details of the transformer do not form part of the present invention, a merely diagrammatic showing is employed.

Positioned at the upper end of the tube B is an outwardly extending housing member including the lower fiat portion E having a vertical circumferential flange E and an upper portion E' overlapping the flange E as at E provided with an inclined wall E E5 indicates a handle whereby the entire portable unit may be moved about. Positioned within the housing member E and conforming generally to the inclined portion E is any suitable indicating and control d-rum G with an inclined wall G The drum G is mounted at the upper end of a shaft the lower end of which connects to the shaft A through the universal joint generally shown as G This universal joint may not be necessary, but it'tendsto prevent strains which would throw the condenser plates out of alignment. G indicates abearing bushing for the upper end of the shaft G and G a hub member for the drum G, secured to the upper end of the shaft G and resting upon the upper end of the bearing G Means for rotating the drum include a shaft H having a knob H thereupon. H is a collar which may be fixed upon the shaft and H an opposed collar adapted to be thrust by the spiral spring H against the edge of the drum G, whereby it is clamped between the two collars. When it is' so clamped, rotation of the knob H serves to rotate the drum and thus actuate the condensers A H diagrammatically indicates a variable resistance adapted to be employed as a volume con troIand adapted to be actuated for example by the knob H This can be connected so as to shunt the grid circuit of the first tube shown in Figure 4.

H indicates any suitable switch for turning the device on and off. It will be understood that the switch H opens the circuit both in the unit enclosed within the movable member and in the relatively fixed housing, thus controlling the entire set.

The drum is provided with a scale G or may be provided with two complete scales at opposite sides thereof, these scales being visible for example through one or more apertures G in the inclined portion E of the upper housing. When two such apertures are used, they are preferably at opposite sides of the wall E C indicates a housing or container the lower edge of which rests upon the base A, the upper portion inwardly extending until, as at C it approaches the tube B It is exterio-rly screw threaded as at C to receive threads C upon D the filament current for the tube I a securing or closure member C the upper edge of which is in close sliding engagement, as at C with the exterior of the tube B It will be understood that the two members above described may be upwardly moved as a unit, in order to give access to the interior of the housing. The housing so formed is shown as round in crosssection. It will be realized, however, that the particular form herein shown is optional and mainly for the purpose of obtaining anornamental appearance and a very wide range of forms of container may be used.

Referring to the semi-portable unit or housing shown at the right hand of Figure l, L indicates any suitable box or housing with which is associated the cover L and the handles L and the loud speaker L As herein shown the box is made portable, although, because of its weight and size, it is not so readily portable as the portable unit proper.

If desired, it may be located in a cabinet or under a table, or in a closet or anywhere else Where it will be out of the way. If, as may be the case, a loud speaker is associated with it, or even within it, it will of course have to be positioned in such location as to permit the loud speaker to be heard by the operator or listeners.

Figure 4 represents a wiring diagram of the radio-frequency amplifier and detector contained in the portable unit shown in Figures 1 to 3.

The three radio frequency tubes are indicated as L The transformers C are employed for couplingthe tubes together. The circuit is of the conventional neutralized tuned radio frequency type. I is the detector tube.

' D is a transformer with two secondary windi-ngslD and D The winding D supplies the filament current for the tubes I, and the winding D is the primary coil of the transformer D.

The volume control is shown in Figure 4 at H and may consist of a variable resistance shunted across the grid circuit of the first tube to which the antenna is connected. Other volume control means may be employed if desired. 1 is a jack located on the portable unit, to which all the connections from the radio frequency and detector portion of the set are brought. I is a cable terminating at one end in a plug I suitable for insertion in the jack I On the other end of the cable I is a plug I suitable for insertion in a jack I located on the semi-portable unit, shown at the right of Figure 1.

Referring to Figure 5, the fixed or semi-portable unit contains three audio amplifying tubes K, anda rectifier tube Kl. A resistance coupled amplifier is here shown, but it will be of course understood that other forms of audio amplifier may be employed. K is a transformer having one primary coil K and one high voltage secondary winding K The filament heater winding "K supplies the filament current to the rectifier tube K These windings are connected through the tube K to a filter circuit K which cooperates with the transformer K and the tube K to form a B supply unit for both the portable and semi-portable portions of the set. K is a secondary winding on the transformer K which supplies the filament current of the audio power tube K. The windings K and K supply filament current to the two preceding tubes. K is a binding post on the semi-portable unit to which the antenna is connected. K is a similar binding post to which a. groundconnection is made. K are It will be seen that the primary coil K of the transformer K and the primary coil D of the transformer D are connected in parallel. One

side of the line K is connected to one side of the parallel transformerprimaries. The other side of the line K is connected to the other side of the parallel primaries through the switch H located with the rest of the controls in the portable unit. When the switch H is opened the current supply to the transformer D and the transformer K is cut off simultaneously. The switch H is therefore adapted to start and stop the complete set. The same effect can be secured by connecting the primary D and the primary K in series and in series with the switch H This will however make necessary the design of the primaries D and K to supply different amounts ofenergy with the same primary current.

Referring to the wiring connections between the two units, it will be seen that the wire I connects to the grid of the tube I at one end and extends to the jack I where it is engaged by a proper terminal on the plug I and, through the cable I with the plug I This is plugged into the jack I on the semi-portable unit, the proper terminal of which is connected by a wire to the binding post K to which the antenna is attached. The circuit of the wire I extends, similarly, through the jacks and plugs and the cable 1 to the semi-portable unit where it connects to a point of proper potential on the B filter cir cuit K whereby the B energy for the tubes I is supplied from the transformer and filter system K K in the semi-portable unit. The circuit of the wire I also extends, through the jacks, plugs and cable I to the grid of the first audio-tube K. It will be seen that in this way all of the leads to the portable unit connect through one cable I which can be detached either from the portable or the semi-portable unit or both, by means of the plugs and jacks I I I', I

The connection I which'carries the output current from the detector tube I to the first audio amplifying tube K is to some degree sensitive to an alternating current field. It may therefore be necessary in some cases to shield this connection particularly with respect to the alternating current leads I I This canbe'done conveniently by enclosing the lead I in a metal sheathing,

this metal sheathing being connected to the ground and constituting the conductor I I have however secured satisfactory hum-free operation without employing this sheathing.

If a wire I 'c0nnected to the ground is run through the cable the capacitative field around the wires I and I is considerably reduced. Twisting the wires I and I so that the wire I does not link with them prevents magnetic coupling. If further shielding is desired the ground wire I may be made in the form of a braided wire tube and the wire I passed through the center of it. This will completely shield it from the action of the wires I and I It has been found by test that no detrimental influence results from passing the wire 1 connected to the antenna K through the cable, with the possible exception of a slight loss in antenna energy which is not especially objectionable. I is a condenser one side of which is connected to the wire I and the other side to ground. This by-passes any radio frequency energy present in the plate circuit of the tube I thus largely preventing it from passing to the cable I It will be realized that whereas I have described and shown a practical and operative device, nevertheless many changes may be made in the size, shape, number and disposition of parts without departing from the spirit of my invention and in details of wiring, circuit and arrangement of parts, and even in distribution of the various parts between the two units. 1 It will be therefore realized that I wish my description and drawings to be taken as in a broad sense illustrative and diagrammatic, rather than as limiting me to the particular description and showing herein contained.

For example where in the claims the housing is described as being located adjacent the floor that I wish such terms including a housing actually resting on the floor and also a housing spaced above the fioor, for example positioned upon legs or intermediate supports, provided that such housing, and the parts therein, are still near enough the floor to maintain the center of gravity of the set sufficiently low to maintain a high degree of stability.

I claim:

1. A remote control radio receiver comprising a central unit and a separate control unitconnected together electrically by a multi-conductor cable, a variable reactance tuning circuit and a thermionic tube in said control unit, a sound reproducer and alternating current supply means in said central unit, a step-down transformer in said control unit for supplying filament current to said thermionic tube, and a pair of conductors in said cable carrying alternating current to said transformer at a voltage higher than the voltage supplied to said tube. 3

2. A remote control radio receiver comprising a central unit and a separate control unit connected together electrically by a multi-conductor cable, a variable reactance tuning circuit and a thermionic tube in said control unit,v a sound reproducer and alternating current supply means in said central unit, a step-down transformer in said control unit for supplying filament current to said thermionic tube, a pair of conductors in said cable. carrying alternating current to said transformer at a voltage higher than the voltage supplied to said tube, and a switch in said con- 'trol unit for turning off said alternating current.

3. A radio receiving set comprising two relatively movable assemblies, thermionic tube means for amplifying and detecting signal'current and,

tuning mechanism in one assembly, and one or more audio frequency tubes in the other assembly, a single flexible cable extending to. the first said assembly, said cable including a pair of alternating current power wires for furnishing filament power to said thermionic tube means and a conductor for conveying amplified detected currents from the first said assembly to the assembly containing one or more audio frequency tubes and a ground conductor and an antenna conductor, means associated with the last said assembly'for connecting the ground conductor and antenna conductor to an external ground and to an external antenna respectively, and means to prevent amplified radio frequency currents from entering upon any conductor of said cable.

4.. A- radio receiving set comprising two relatively movable assemblies, tuning mechanism and thermionic tube means for amplifying and detecting signal current in one assembly, and one or more audio frequency thermionic tubes in the a other assembly, a. single flexible; cable extending to the assembly containing tuning mechanism, said cable including a conductor constituting part. of an untuned. circuit carrying alternating signal currents, an antennavconductor, a, conductor carrying detected current, and. other con.- ductors carrying alternating power current included within the same cable, and means associated with the assembly having one or' more audio frequency thermionic tubes for connecting said antenna conductor to an external antenna.

5. A radio receiving set. comprising two relatively movable assemblies, tuning mechanism and radio frequency amplifying and detector thermionic tubes in one assembly, and one or more audio frequency thermionic tubes in the other assembly, a single flexible cable extending to the assembly containing tuning mechanism, said cableincluding a conductor constituting part of an untuned circuit carrying alternating radio frequency signal currentsand means to isolate all of the conductors of said cable from tuned or amplified radio frequency currents.

6. A radio receiving equipment consisting of two relatively portable housings connected together by a single flexible cable of sufficient length to permit one of said housings to be moved from place to place about a room, conductors carrying alternating power current in said cable, an antenna conductor extending into the stationary housing. and thence through said cable to the portable housing and forming a part of a radio frequency circuit, radio frequency amplifying and detecting means in the portable housing, means to prevent amplified radio frequency currents from entering upon any of the conductors of said cable, whereby feed-back to said radio frequency antenna circuit is prevented in the cable, and amplifying means in the other housing.

'7. A radio receiving. equipment comprising two containers, one of which is readily portable and contains tuning, amplifying and frequency changing means, a single cable having a plurality of conductors connecting said tuning, amplifying and frequency changing means in said portable container with the other said container, a conductor in said cable carrying radio frequency currents, an external antenna connected to last said conductor at said other container, a second conductor in said cable carrying audio frequency currents produced by the passage of said radio frequency currents through the said tuning, amplifying and frequency changing means in said portable container, means excluding any objectionable amount of said radio frequency currents from said conductor carrying audio frequency currents. means for excluding any amplified radio frequency currents from any said conductor in said cable to prevent feed-back effects, and amplifying means in the other container.

8. A radio receiving equipment comprising two or more associated containers, one of said containers being readily portable and constituting a housing for radio frequency tuning mechanism and for radio frequency amplifying devices, said container being electrically connected with the other parts of the radio receiver by a single cable, one conductor of said cable carrying radio frequency signal current to be amplified and tuned, another conductor of said cable carrying amplified signal currents at different frequencies from that of the first mentioned conductor of the cable, other conductors of said cable carrying alternat'ing power current, means to prevent signal currents of like frequency but at different degrees of amplification from simultaneously entering the conductors of said cable, amplifying means in the other container, and an external antenna connected to the first said conductor of the cable, at said other container.

9. A radio receiving set comprising two relatively movable assemblies, one or more radio frequency tubes, tuning mechanism and a detector tube in one assembly, and one or more audio frequency tubes in the other assembly, a single flexible, cable extending to the assembly containing one or more radio frequency tubes and tuning mechanism, said cable including a pair of alternating current power wires for furnishing filament power to said radio frequency tube or tubes, and a conductor for conveying amplified currents of reduced frequency from the assembly containing one or more radio frequency tubes to the assembly containing one or more audio frequency tubes, and a ground conductor and an antenna conductor, means to prevent amplified radio currents of the frequency of the antenna currents from entering upon any conductor of said, cable, an external antenna connected to the antenna conductor and an external ground connected to the ground conductor at the assembly containing one or more audio frequency tubes.

10; A radio receiving set comprising a relatively movable assembly and an assembly adapted to have a relatively fixed location, tuning mechanism and one or more thermionic tubes including a frequency changing device in the relatively movable assembly, and one or more audio frequency tubes in the relatively fixed assembly, a single flexible cable extending to the relatively movable assembly, said cable including a pair of alternating current power wires for furnishing filament power to said tube or tubes in the relatively movable assembly and a conductor for conveying amplified currents of reduced frequency from the relatively movable assembly to the relatively fixed assembly, and a ground conductor and an antenna conductor, means to prevent amplified radio currents of the frequency of the antenna currents from entering upon any conductor of said cable, and means on the relatively fixed assembly for connecting said ground conductor and said antenna conductor to an external ground and to an external conductor, respectively.

11. A radio receiving equipment consisting of two relatively portable housings connected together by a single flexible cable of sufiicient length to permit one of said housings to be moved from place to place about a room, a floor engaging member at one end of last said housing, control and indicating means at the other end of last said housing, said cable being connected to last said housing adjacent said fioor engaging member, and an antenna conductor extending into the stationary housing and thence through said cable tothe portable housing and forming part of a radio frequency circuit, radio frequency amplifying means, and a detector in the portable housing, means to prevent amplified radio currents of the same frequency as the antenna from entering upon any of the conductors of said cable, whereby feed-back to the radio frequency antenna circuit is prevented in the cable, and amplifying means in the other housing.

12. A radio receiving equipment comprising two containers, one of which is readily portable and contains tuning, amplifying and frequency changing means and is provided with a floor engaging member at its lower end and control and indicating means at its other end, a single cable attached to said portable container adjacent said floor engaging member having a plurality of conductors connecting said tuning, amplifying and frequency changing means in said portable container with the other said container, a conductor in said cable carrying currents of carrier wave frequency, a second conductor in said cable carrying currents of substantially lower frequency produced by the passage of said currents of carrier wave frequency through the said tuning, amplifying and frequency changing means in said portable container, other conductors in said cable carrying alternating power current, means for excluding any objectionable amount of currents of carrier wave frequency from said conductor carrying currents of, substantially lower frequency, means for excluding any amplified currents of carrier wave frequency from any conductor in said cable to prevent feed-back effects, amplifying means in the other container and means at said other container for attaching an external antenna to the first said conductor of said cable.

13. A radio receiving equipment comprising two containers, one of which is readily portable and contains tuning, amplifying and frequency changing means, a single cable having a plurality of conductors connecting said tuning, amplifying and frequency changing means in said portable container with the other said container, a conductor in said cable carrying currents of carrier wave frequency, a second conductor in said cable carrying currents of substantially lower frequency produced by the passage of said currents of carrier wave frequency through the said tuning, amplifying and frequency changing means in said portable container, means for excluding any objectionable amount of'currents of carrier wave frequency from said conductor carrying currents of substantially lower frequency, amplifying means in the othercontainer, and means on said other container for connecting said conductor carrying currents of carrier wave frequency to an external antenna.

14. A radio receiving equipment comprising two containers, one of which is readily portable and contains tuning, amplifying and frequency changing means, a single cable having a plurality of conductors connecting said tuning, amplifying and frequency changing means in said portable container with the other said container, a conductor in said cable carrying currents of carrier wave frequency, a second conductor in said cable carrying currents of substantially lower frequency produced by the passage of said currents of carrier wave frequency through the said tuning, am plifying and frequency changing means in said portable container, other conductors in said cable carrying alternating power current,.means for excluding any currents of carrier wave frequency at objectionably high voltage from the conductor carrying currents of substantially lower frequency, amplifying means in the other container, and means on said other container for connecting the conductor carrying currents of carrier wave frequency to an external antenna.

15. A radio receiving equipment comprising two containers, one of which is readily portable and contains the tuning mechanism of said receiving equipment, a single cable including all of the conductors connecting said portable container and tuning means with the other said container, one of said conductors in said cable carrying a radio signal of carrier frequency, a second of said conductors in said cable carrying a-signal of lower frequency which is produced by the passage of said first signal through the apparatus and tuning means in said portable container,-

means for excluding any currents of carrier wave frequency at objectionably high voltage from said conductor carrying the lower frequency, amplifying means in the other container and means on said other container for attaching the cable carrying the radio signal of carrier frequency to an external antenna. I

16. A radio receiving equipment comprising two or more associated containers, one of said containers being readily portable and adapted to rest upon the floor, said container consisting of a housing for radio frequency tuning mechanism and for radio frequency amplifying devices, controls for said mechanism and devices located at the upper end of said housing, said housing being electrically connected with the other parts of the radio receiver by a single cable, one conductor of said cable carrying radio frequency signal current to be amplified and tuned, another conductor of said cable carrying amplified currents at different frequencies from that of the first mentioned conductor of the cable, other conductors of said cable carrying alternating power current, means to prevent currents of like frequency but at different degrees of amplification from simultaneously entering the conductors of said cable, amplifying means in the other container, and an external antenna connected to theconductor carrying radio frequency signal current at said other container.

17. A radio receiving equipment comprising two containers, one of said containers being readily portable and adapted to rest upon the floor, said container providing a housing for tuning, amplifying and frequency changing means, controls for said tuning, amplifying and frequency changing means located at the upper end of said housing, a single cable having a plurality of conductors connecting said tuning, amplifying and frequency changing means in said portable container with the other said container, a conductor in said cable carrying currents of carrier wave frequency, a second conductor in said cable carrying currents of substantially lower frequency produced by the passage of said currents of carrier wave frequency through the said tuning, amplifying and frequency changing means in said portable container, means for excluding any objectionable amount of currents of carrier wave frequency from said conductor carrying currents of sub- 1 stantially lower frequency, and amplifying means in the other container.

. 18. A radio receiving equipment consisting of two housings connected together by a single flexible cable, an antenna conductor extending from one housing and thence through said cable to the other housing and forming part of a radio frequency circuit, other conductors extending through said cable carrying alternating power current, radio frequency amplifying and detecting means in the last said housing, means to prevent amplified radio currents of the same frequency as the antenna from entering upon any 

